Water Resources and Conservation

Surface Water

The City of Petaluma is located 35 miles north of San Francisco in Sonoma County on the Highway 101 corridor. The City limit encompasses approximately 14 square miles and is situated in the upper Petaluma River watershed. The lower 12 miles of the Petaluma River flows through the Petaluma Marsh, the largest remaining salt marsh in the San Pablo Bay.

Surface water refers to water occurring in lakes, rivers, streams, or other fresh water sources. Surface water remains a significant water resource in the United States.

Surface water is naturally replenished by precipitation and naturally lost through discharge to evaporation and sub-surface seepage into the groundwater. This process is commonly known as the hydrologic cycle.

The management of surface water occurs by two means: naturally through creeks; streams; rivers; lakes; and artificially in urban areas through man-made conduits such as channels, ditches and pipes. The City of Petaluma's storm drain system consists of ditches, natural and improved channels, pipes, and culverts, all discharging ultimately into the Petaluma River which terminates into the San Pablo Bay.

The Petaluma River Watershed encompasses approximately 146 square miles and supports beneficial uses for freshwater aquatic habitat, preservation of threatened and endangered species, wildlife habitat, and water recreation. Impacts from urban growth, construction, land development, atmospheric deposition, and agricultural activities contribute a variety of pollutants to the surface water runoff, in which trash and sediment place the Petaluma River on the 2008 Clean Water Act's Section 303(d) list.

The City has developed and adopted a Storm Water Management Plan which intends to protect and enhance the water quality of watercourses and water bodies in a manner pursuant to and consistent with the Federal Water Pollution Control Act (33 U.S.C. Section 1251 et seq.). The Stormwater Management Plan reduces pollutants in stormwater discharges to the maximum extent practicable (MEP) and by prohibiting non-stormwater discharges to the city's municipal separate storm sewer system (MS4).